1. Field of the Invention
The present invention relates to control apparatus and a method of operation of an air conditioning system. More specifically, the present invention concerns providing means for selectively reducing delay periods regulated by an electonic control to enable a serviceman to cycle an air conditioning unit between various modes of operation without waiting for the full delay periods.
2. Description of the Prior Art
Air conditioning systems as used herein refers to systems for heating, cooling, ventilating, humidifying, dehumidifying and cleaning air that may be circulated to a space or utilized in a process. In certain types of air conditioning systems delay intervals between different modes of operation are deemed desirable. In an air conditioning system including a refrigeration circuit which may be reversible for supplying heating and cooling to a space it has been found desirable to incorporate delay periods when switching between various modes of operation.
Specifically, delays may be utilized between intervals for defrosting the heat pump system and operating in the heating mode of operation. These delays may be both a minimum time between defrost cycles and a maximum time between defrost cycles. A short cycling delay to prevent the air conditioning compressor from repeated startups and shutdowns may involve a delay interval after the operation cycle during which the compressor may not be energized.
Other delays include delays for determining current reference values after startup to assure the system has settled into steady state operation. Another delay such as delaying for a period after startup before determining low current may also be utilized.
A serviceman in diagnosing any potential problems with an air conditioning unit may desire to operate the unit to determine what malfunction, if any, is present. The serviceman will typically desire to operate the unit in various modes of operation. As the unit is operated in the selected modes the delay periods provided when switching between modes of operation will occur. It is wasteful of the serviceman's time to have him wait for five or ten minutes or as much as six hours between defrost cycles to have the delay period expire before the next mode of operation may occur or before the compressor may be restarted.
The invention as described herein discloses a jumper for generating a speedup signal to greatly decrease the length of the various delay periods such that the serviceman may quickly observe the unit running in different modes of operation.